How would the transfer window have looked for Arsenal had Mesut Ozil not signed a new £300,000-a-week deal to commit himself to the club until 2021? Alexis Sanchez and Olivier Giroud out, Pierre-Emerick Aubameyang and Henrikh Mkhitaryan in.Time will tell if Arsene Wenger has emerged from the January sales with a stronger squad than he started the New Year with at the Emirates.Either way, persuading Ozil to sign a new contract may prove to be the key piece of business in a season that has seen Arsenal's forward line transformed by the arrivals of Aubameyang, Mkhitaryan and Alexandre Lacazette.It has come at a price.The gifted German playmaker is now one of the biggest earners in the Premier League.But that's what it takes to get, or keep, the star players – as Manchester United found out in gazumping Manchester City to sign Sanchez in a deal worth a total of £600,000 per week including bonuses and image rights.It was imperative that Wenger kept one of his two prize assets.But, whereas Sanchez made no secret of his desire to leave and became increasingly disruptive behind the scenes, Ozil has simply got on with it.If anything, the former Real Madrid star has been even more influential on the pitch for Arsenal in recent months.In the end he 'let my heart decide', although it's safe to say that he was swayed by a significant pay rise as well.Wenger acknowledged the importance of the player's decision, admitting that Arsenal are in a 'tricky period'.Securing Ozil's future after negotiations appeared to have hit a wall last year could tip the balance in their favour.'Many predicted he wouldn't commit and not sign,' added the Arsenal boss.'It's good news for us.If you can keep a player of that calibre, of course it's good news.We expect him to take responsibility to lead the club to success.' All in all, it could herald a bold – and possibly final – chapter in Wenger's time at the Emirates.A last hurrah for the Frenchman who has appeared to be on the brink of leaving the club in recent years.Wenger can only hope that Arsenal emerge from the reshuffle in better shape than they were before.Aubameyang, the club's record signing at £56m, is clearly capable of great things although there are concerns over his temperament.Mkhitaryan is better suited to Arsenal than United, it has been said, and now is the time to prove it.The Armenian had many admirers at Old Trafford.Unfortunately for him, Jose Mourinho was not one of them, and a parting of the ways had seemed inevitable for some time.Unlike Aubameyang, he has 18 months' experience of playing in the Premier League under his belt, and will be expected to hit the ground running.Lacazette has scored nine goals so far, but it's fair to say that more was expected of the Frenchman when he arrived from Lyon last summer for a then record £52.7m.There is still time for Lacazette to be a success this season, and that rather sums up Arsenal's situation at the moment.Sixth in the Premier League, eight points behind Che